Participants
| Role | Name | HCID | Charge |
|---|
| Reactant | Triethylamine | HCID 8471 | — |
| Reactant | 2-Chloro-3-nitropyridine | HCID 79613 | — |
| Reactant | L-Alanine, ethyl ester, hydrochloride (1:1) | HCID 2724356 | — |
| Solvent | Ethanol | HCID 702 | — |
| Product | HCID 14390515 | HCID 14390515 | 0.1% |
Reaction Steps
A suspension of 2-chloro-3-nitropyridine (68.6 g, 0.434 mole), (S)-alanine ethyl ester hydrochloride (100 g, 0.651 mole) and triethylamine (103.7 g, 1.03 mole) in 95% ethanol was heated at reflux for 4.5 hours, during which time a dark yellow solution formed. The reaction mixture was stirred at room temperature overnight and then refluxed for an additional 2 hours. The solvents were evaporated under reduced pressure, and the resulting solid was triturated in ethyl acetate, filtered, and rinsed with additional ethyl acetate. The filtrate and washings were combined and washed three times with water, dried over sodium sulfate, filtered, and evaporated to an oil weighing 107 g (quantitative yield). The oil was eluted through 600 g of silica gel, using ethyl acetate as the eluent, and evaporated to an oil. A 3.5-g portion of the oil was dissolved in isopropyl alcohol and acidified with ethereal hydrogen chloride. The mixture was evaporated and redissolved in acetonitrile. Addition of isopropyl ether caused a solid to precipitate. The solid was collected by filtration and its mother liquor was evaporated and the residue was triturated in ethereal hydrogen chloride. A yellow solid formed which was collected by filtration. Upon standing, more solid formed in the mothor liquor. This solid was collected by filtration, rinsed with diethyl ether and dried under high vacuum to give 0.14 g of title compound, mp >260° C. (darkens 178°-185° C.).
Provenance & Evidence
| DOI | 10.6084/m9.figshare.5104873.v1 |
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| Patent number | US04948800 |
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| Source dataset | uspto-grants-1990_08 |
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| ORD ID | ord-0662467691c3415b89e99084b18a98c1 |
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| Source note | uspto-grants-1990_08 |
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